The German government was furious when it emerged last month that Sellafield had supplied fuel rods with falsified data to a German nuclear power plant.

The plant in Unterweser was shut down so the rods could be removed.

But doing any further business with Sellafield is now in doubt.

Officials from British Nuclear Fuels have been summoned to the German Environment Ministry to answer searching questions on those lapses in safety.

Germany is currently BNFL's second biggest customer for reprocessing nuclear waste.

If it decides to pull out of its valuable contracts, the future of Sellafield could be further jeopardised.

The Greens and the German government are determined to put an end to nuclear power.

Doubts over safety standards at Sellafield have given them a strong argument for stopping shipments of nuclear waste to Britain.

Japan ban

Germany is British Nuclear Fuels' second biggest customer after Japan.

Japan also halted shipments from Sellafield after BNFL admitted workers checking the size of mixed plutonium and uranium oxide (Mox) fuel pellets, had used old figures instead of monitoring every pellet.

Japan suspended all Mox imports from the UK as a result of the safety lapses, and BNFL Chief Executive John Taylor resigned.